Electric heat-alarm



(No Model.)

M. MARTIN.

ELECTRIC HEAT ALARM.

10.272,893@ F. Patentedfeb-zma8s.

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MQTT'L'J Martha;

N, PETERS. Phowmhographm. Waahmgmm D. C.

UNITED STATES PATENT OFFICE.

MORRIS MARTIN, OF MAIIDEN, MASSACHUSETTS, ASSIGNOR or Two-TIIIRIIS To EDWIN A. .IEFFERTT AND FREDERICK o. .IEFFERY, ROTE OF BOSTON, MASSACHUSETTS.

ELECTRIC HEAT-ALARM.

SPECIFICATION forming part of Letters Patent No. 272,898, dated February 27, 1883.

Application filed September 25, 1882. (No model.)

To alt Vwhom it may concern: The dial A, being a metallic plate fitted in a Be it known that I, MORRIS MARTIN, of wooden annulus or case,D,isto be electrically Malden, in the county ot' Middlesex, ot' the insulated from the metallic frame E, that snp- Commonwealth ofMassachusetts,have inventports the mechanism for operating the hand 55 5 ed a new and useful Improvement in Electric B, the insulators being` shown at FF as pieces Heat-Alarms; and [do hereby declare the same ot' vulcanized india-rubber interposed between to be described in the following specilication such dial and frame. A wire, G, leads from and represented in the accompanying drawthe dial to a cireuitwire binding-post, H, proings, Ot' whichvided with a clamp-screw,f, suc'h post being' 6o Io Figure lis a front elevation, and Fig. 2 a extended from the wooden case D. Another transverse and central section, of a metallic such bindingpost, H', provided with a clampdial thermometer provided with myinvention, screw,f, also projects from the case l), and the nature ot' which is detined in the claims has a wire, I, extending from it to the Inetallic hereinafter presented. Figx is a rear view of frame E. There are piroted to the dial, so as 65 .I5 the thermometer with the back of its case reto he in electric connection with it, concentrimoved. cally with the arbor ofthe hand B, but wholly The Object ot' the invention is to cause the out of contact with such arbor, two other auxcircuit ot' an electrical alarm to be closed at iliary hands, K L, each being adapted so as to any desirable temperature indicated by the be capable of being swung around the divided 7o zo main hand of the dial of the aforesaid thercircle ofthe dial from one division to another mometer,tl1e closing of the circuit causing the thereof. Each ofthe hands K L has its outer alarm mechanism to be thrown into operation end bent upward at a right angle into or above so as to setuid an alarm. the plane of rotation of the hand B.

, Electrical circuit-wires to lead from thc ther- The operation of the apparatus may be thus 75 z5 mometer or its connectionposts to a battery described: lf we suppose it to have applied and an alarm apparatus dofnot constitute any to its binding-posts the circuit-wires of a galpart of my inventiomand may be ot' any wellvanic battery and an'electrical alarm apparaknown kind,thetwo cincuit-wires being` simply tus, and the dial auxiliary hands K L be set shown in part in Figfi of the drawings in their upon any two divisions ot' the dial, it will be 8o 3c, application tothe connection-posts ofthe wires seen that whenever the main hand may be ot' the metallic thermometer. This thermomemoved against the turned-up portion of either ter, in its general construction, is essentially of the said auxiliary hands the electrical cirlike that as made by the Auburndale Vatch cuit will be closed, and as a consequence the Company, and known by the name ot' the mealarm apparatus will be ptit in operation. The 85 35 tallic thermometer,it having adial,A,an indiupturned ends of the hands K L prevent the cater-hand, B, and mechanism (l to move the pointer from passing beyond, and hence as said hand around on the dial, such mechanism, soon as the limit is reached the alarm is soundproperly sustained by a bar, S, extending ed and continues. While the main hand may across the case, being put in operation by exbe out of contact with either ot' the auxiliary 9o 4o pansion or contraction of parts of it-viz., two hands the electrical circuit will be open. From metallic bows-such expansion and contracthis it will be seen that should we desire to tion being induced by changes in temperature. have the circuit closed at any degree ot' tem- These bows are shown at a c. Each of them perature, we have only to move one ot' the auxis stationary at the outer end of it, and they iliary hands to that degree on the dial,and on 95 45 have their inner ends properly adapted to two the main hand being moved up to the auxilarms of a lever, b, to cause such lever to be iary hand by the increase or decrease of the turned one way by them while they may be temperature the circuit will be closed. With expanding, and turned the other way while the two auxiliary hands the circuit may be they may be contracting. This lever carries closed at either of two degrees ot' temperature Ioo l 5o a toothed sector, c, that engages with a pinio'n, between which the :nain hand may be ou the @fixed 0n the arboreof the indicatonhand B. dial, and to which the two auxiliary hands ma-y be set. Thus,if the alarm is to be sounded when the temperature is 1000 and also when it may fall to 600, We should move one auxiliary hand to the division indicative of 1000 andthe other to the division indicative of 600. Should the temperature rise to 1000 or fall to 600, the

circuit will be closed.

I am aware that an electric heat-alarm has been devised in which a thermometer havingr insulated portions is used. I lay no broad claim thereto; but

I claim* l. rPhe dial-thermometer havingits metallic dial electrically insulated from its indicatorhand and the operative mechanism thereof', and provided With one or more auxiliary hands having upturned ends, as described, applied to it and disconnected With the main hand,in combination with the Wires ot'an electric alarm, one Wire being connected with the dial, the

erases other with the indicator-hand, substantially as set forth.

2. The dial-thermometer. provided with wires G I, the former connected to the dial-plate and the latter to the indicator-hand, and electrical circuit-Wire bindingposts H H', adapt ed to it as set forth, and having` its metallic dial electrically insulated from its indicator-hand and the operative mechanism thereof, and provided with one or more auxiliary hands having upturned ends, as described, applied to it and disconnected with the main hand, in combination with the Wires of an electric alarm, one Wire being connected to the binding-post H and the' other to the post H', as set forth.

MORRIS MARTIN.

Witnesses:

HENRY W. WILLIAMS, JosEPH IsHBAUeH.

M en 

